A lateral-cutting can opener is a cutting tool able to laterally cut the rim of a can. This can prevent the blade of the cutting tool from extending into the can to contaminate the food. Besides, the opening of the can won't have any sharp point, and the can lid can be reused. The lateral-cutting can opener is safe and hygienic for use and the food can be preserved with ease, so it is popular by consumers.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to develop lateral-cutting can openers, such as Taiwan Patent Publication No. 327896 and U.S. Pat. No. 5,946,811 titled “SIDE CUTTING CAN OPENER WITH A DOUBLE GRIP”; Taiwan Patent Publication No. 564884 and U.S. Pat. No. 6,829,832 titled “SINGLE-HANGLE CAN OPENER”. Regarding Taiwan Patent Publication No. 327896, referring to FIG. 1, a main body 91 of a can opener 9 is provided with a cutter wheel 92 and a shaft hole 911. The shaft hole 911 is provided with a traction wheel 93. A rotary shaft 931 of the traction wheel 93 is orderly inserted through a spring 94, a sleeve 95, a washer set 96, and a hexagonal slide block 97. The distal end of the rotary shaft 931 is formed with threads 932 to mate with a positioning sleeve 98. The hexagonal slide block 97 is sleeved with a rotary lever 99. The rotary lever 99 is rotated clockwise to bring actuation of the hexagonal slide block 97 (referring to FIG. 2), enabling the positioning sleeve 98 to move from the lowest to the highest of a concave slope 971 of the hexagonal nut 97. The traction wheel 93 is moved toward the main body 91 to shorten the distance D, so that the rim of the can A is pushed toward a cutter wheel 92, enabling the cutter wheel 92 to cut into the outermost thickness of the can A so as to sever the lip of the rim of the can A.
However, the distance defined between the traction wheel 93 and the cutter wheel 92 of the conventional can opener 9 is only for the thickness of the rim of a common small can. (The total thickness of a common can is about 1-1.2 mm, namely, the thickness of a single-layer is 0.2-0.22 mm). When the can opener 9 is used to open a can B having a thicker rim (such as, a milk powder can of more than 1.5 kg, a tomato can having a diameter of more than 15 cm, or the like), referring to FIG. 3, because the rim of the can is thicker, it is laborious to rotate the rotary lever 99. Sometimes, the rotary lever 99 cannot be rotated. As a result, the can B cannot be severed smoothly. It is necessary to adjust the space between the traction wheel 93 and the cutter wheel 92. Next use, when the can opener is used to open a can A having a thinner rim (such as a condensed milk can), the cutting depth of the cutter wheel 92 is not enough for cutting the outermost thickness of the rim of the can to cause a failure in severing the can A.
In view of the shortcomings of the prior art and the previous lateral-cutting can openers invented by the applicant, the can opener is subjected to the size of the can and the thickness of the rim of the can. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve this problem.